Question

In nitroprusside ion, the iron and NO exist as $F{e}^{+2}$ and $N{O}^{+}$, instead of $F{e}^{+3}$ and $NO$. The given conclusion can be drawn by:

• A. estimating the concentration of iron
• B. measuring the concentration of $C{N}^{-}$ ion
• C. measuring the solid state magnetic moment
• D. thermally decomposing the compound

Answer 1

The correct option is C measuring the solid state magnetic moment

The nitroprusside ion is $\left[Fe\right(CN{)}_{6}N{O}^{+}{]}^{2-}$. The solid state magnetic moment measurement reveals the presence of 4 unpaired electrons in Fe, which must be then in $F{e}^{2+}\left(3d^6\right)$, and not $F{e}^{3+}\left(3d^5\right)$.